CBMEM: Add timestamp_reinit()

This avoids the need for separate timestamp_reinit() calls made
via CAR_MIGRATE() that is not implemented for ARM.

Change-Id: Ia683162f3cb5d3cb3d4b7983a4b7e13306b0cfc8
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/8033
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@google.com>
Tested-by: build bot (Jenkins)

src/lib/hardwaremain.c

@@ -181,8 +181,6 @@ static boot_state_t bs_post_device(void *arg)
 	dev_finalize();
 	timestamp_add_now(TS_DEVICE_DONE);
 
-	timestamp_reinit();
-
 	return BS_OS_RESUME_CHECK;
 }